linux-kernel - Re: [PATCH v6 07/11] drm/mediatek: dp: Avoid mutex locks if audio is not supported/enabled

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Date:   Thu, 20 Jul 2023 15:05:02 +0200
From:   Alexandre Mergnat <amergnat@...libre.com>
To:     AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@...labora.com>, chunkuang.hu@...nel.org
Cc:     p.zabel@...gutronix.de, airlied@...il.com, daniel@...ll.ch,
        matthias.bgg@...il.com, dri-devel@...ts.freedesktop.org,
        linux-mediatek@...ts.infradead.org, linux-kernel@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, kernel@...labora.com,
        wenst@...omium.org, nfraprado@...labora.com
Subject: Re: [PATCH v6 07/11] drm/mediatek: dp: Avoid mutex locks if audio is
 not supported/enabled



On 17/07/2023 16:14, AngeloGioacchino Del Regno wrote:
> If a controller (usually, eDP!) does not support audio, or audio is not
> enabled because the endpoint has no audio support, it's useless to lock
> a mutex only to unlock it right after because there's no .plugged_cb().
> 
> Check if the audio is supported and enabled before locking the mutex in
> mtk_dp_update_plugged_status(): if not, we simply return immediately.
> 
> While at it, since the update_plugged_status_lock mutex would not be
> used if the controller doesn't support audio at all, initialize it
> only if `audio_supported` is true.

Reviewed-by: Alexandre Mergnat <amergnat@...libre.com>

-- 
Regards,
Alexandre